MAX2232EEE ,900MHz ISM-Band, 250mW Power Amplifiers with Analog or Digital Gain ControlFeaturesThe MAX2232/MAX2233 low-voltage, silicon RF power' 800MHz to 1000MHz Frequency Rangeamplifi ..
MAX2233EEE ,900MHz ISM-Band, 250mW Power Amplifiers with Analog or Digital Gain ControlELECTRICAL CHARACTERISTICS(V = +2.7V to +5.5V, V = +2.2V, V = V = V = +2V, T = -40°C to +85°C. No i ..
MAX223CAI ,+5V-Powered, Multichannel RS-232 Drivers/ReceiversMAX220–MAX24919-4323; Rev 9; 4/00+5V-Powered, Multichannel RS-232Drivers/Receivers
MAX223CAI+T ,+5V-Powered, Multichannel RS-232 Drivers/Receivers+5V-Powered, MultichannelMAX220–MAX249RS-232 Drivers/Receivers
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MAX223EAI ,+5V-Powered, Multichannel RS-232 Drivers/ReceiversGeneral Description ________
MAX531BCSD+T ,+5V, Low-Power, Voltage-Output, Serial 12-Bit DACsMAX531/MAX538/MAX53919-0172; Rev 6; 2/97+5V, Low -Pow er, Voltage-Output,Serial 12-Bit DACs________ ..
MAX531BEPD ,+5V, Low-Power, Voltage-Output, Serial 12-Bit DACsFeaturesThe MAX531/MAX538/MAX539 are low-power, voltage-' Operate from Single +5V Supplyoutput, 12- ..
MAX531BESD ,+5V, Low-Power, Voltage-Output, Serial 12-Bit DACsApplications______________Ordering InformationBattery-Powered Test InstrumentsERRORPART TEMP. RANGE ..
MAX5322EAI ,+/-10 V, 12-bit, serial, voltage-output DACELECTRICAL CHARACTERISTICS (DUAL SUPPLY)(V = +15V ±5%, V = -15V ±5%, V = +5V ±10%, AGND = DGND = SG ..
MAX532ACPE ,Dual, Serial-Input, Voltage-Output, 12-Bit MDACapplications.' Operates from ±12V to ±15V SuppliesThe MAX532 is specified with ±12V to ±15V power s ..
MAX532ACPE ,Dual, Serial-Input, Voltage-Output, 12-Bit MDACApplications______________Ordering InformationAutomatic Test EquipmentArbitrary Waveform Generators ..
MAX2232EEE-MAX2233EEE
900MHz ISM-Band, 250mW Power Amplifiers with Analog or Digital Gain Control
General DescriptionThe MAX2232/MAX2233 low-voltage, silicon RF power
amplifiers (PAs) are designed for use in the 900MHz
ISM band. They operate from a single +2.7V to +5.5V
supply, allowing them to be powered directly from a 3-
cell NiCd or a 1-cell Lithium-Ion battery. The devices
typically deliver 250mW (+24dBm) of output power at
915MHz from a single +3.6V supply, or 150mW
(+22dBm) from a single +2.7V supply. At +24dBm out-
put power, power-added efficiency (PAE) is 44%.
The MAX2232/MAX2233 provide 24dB of gain, which is
adjustable over a continuous 24dB span via the analog
gain-control pin of the MAX2232 or in two 10dB steps
via the 2-bit programmable gain-control DAC of the
MAX2233. An external capacitor sets the RF output
power envelope ramp time, reducing spurious emis-
sions during power-up and power-down by providing a
gradual change in output power (MAX2232).
The MAX2232/MAX2233 feature a low-power shutdown
mode, which typically draws less than 1µA of supply
current, saving power during “idle slots” in time-division
multiple-access (TDMA) systems. The ΔVSWR of the RF
input in shutdown mode relative to normal operation is
1.2:1. The devices also feature a thermal shutdown
function, enabling the PA to protect itself from excessive
temperature conditions that could damage the IC. A
capacitor to ground limits thermal cycling by setting a
thermal shutdown timeout period.
The MAX2232/MAX2233 are available in a space-sav-
ing, thermally enhanced 16-pin power-QSOP (PQSOP)
package.
Applications900MHz ISM Band
Digital Cordless Phones
Wireless Data
FM Analog Transmitters
868MHz European ISM Band
Features800MHz to 1000MHz Frequency Range250mW (+24dBm) Output Power at 915MHz from
+3.6V Supply+2.7V to +5.5V Single-Supply Operation44% Power-Added Efficiency 24dB Power Gain24dB Analog Gain-Control Range (MAX2232)Three Levels of Digitally Programmed Power Gain
in 10dB Steps (MAX2233)Programmable RF Power Envelope Ramping
(MAX2232)Thermal ShutdownProgrammable Thermal Shutdown Timeout Period0.2µA Low-Power Shutdown ModeLow ΔVWSR in Standby and Shutdown Modes
MAX2232/MAX2233
900MHz ISM-Band, 250mW Power Amplifiers
with Analog or Digital Gain Control19-1470; Rev 0; 4/99
Pin Configuration
Ordering Information
Functional Diagram appears at end of data sheet.
MAX2232/MAX2233
900MHz ISM-Band, 250mW Power Amplifiers
with Analog or Digital Gain Control
ABSOLUTE MAXIMUM RATINGS
DC ELECTRICAL CHARACTERISTICS(VCC = +2.7V to +5.5V, VCTRL= +2.2V, VSHDN= VD0= VD1= +2V, TA= -40°C to +85°C. No input signal applied, unless otherwise
noted. Typical values are at VCC= +3.6V and TA= +25°C.)
AC ELECTRICAL CHARACTERISTICS(MAX2232/MAX2233 Evaluation Kit, VCC= +3.6V, VCTRL= +2.2V, SHDN= VCC(MAX2232), D0 = D1 = VCC(MAX2233),
PRFIN= 0dBm, ƒRFIN= 915MHz, TA= +25°C, unless otherwise noted.)
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
VCCto GND...........................................................-0.3V to +6.5V
SHDN, CTRL, D0, D1 to GND ....................-0.3V to (VCC+0.3V)
IRFIN....................................................................................10mA
RFIN Power (50ΩAC-coupled source)..........................+10dBm
Output Load VSWR.................................................................6:1
Continuous Power Dissipation (TA= +70°C)
16-Pin PQSOP (derate 80mW/°C above +70°C)................3W
Operating Temperature Range...........................-40°C to +85°C
Storage Temperature Range.............................-65°C to +150°C
Lead Temperature (soldering, 10sec).............................+300°C
MAX2232/MAX2233
900MHz ISM-Band, 250mW Power Amplifiers
with Analog or Digital Gain Control
AC ELECTRICAL CHARACTERISTICS (continued)(MAX2232/MAX2233 Evaluation Kit, VCC= +3.6V, VCTRL= +2.2V, SHDN= VCC(MAX2232), D0 = D1 = VCC(MAX2233),
PRFIN= 0dBm, ƒRFIN= 915MHz, TA= +25°C, unless otherwise noted.)
Note 1:Guaranteed by design.
Note 2:Operation outside this range is possible, but not characterized.
Note 3:Gain is monotonic with VCTRL.
Note 4:Input VSWR relative to input impedance in operating mode.
Note 5:Harmonics measured on evaluation kit, which provides some harmonic attenuation in addition to the rejection provided by
the IC. The combined suppression is specified.
Note 6:Time measured from SHDN(MAX2232) low-to-high transition to when output power is within 1dB of final value. Includes
effects of 1% tolerance capacitor.
Note 7:Time measured from SHDN(MAX2232) high-to-low transition to when output power is -20dB of final value. Includes effects
of 1% tolerance capacitors.
Note 8:Time from die temperature dropping below Thermal Shutdown Temperature, TTH, to when the device turns itself back on.
MAX2232/MAX2233
900MHz ISM-Band, 250mW Power Amplifiers
with Analog or Digital Gain Control
Typical Operating Characteristics(MAX2232/MAX2233 Evaluation Kit, VCC= +3.6V, CTRL = VCC, SHDN= D0 = D1 = VCC, PRFIN= 0dBm, fRFIN= 915MHz, TA= +25°C,
MAX2232/MAX2233
900MHz ISM-Band, 250mW Power Amplifiers
with Analog or Digital Gain Control
Pin Description
MAX2232/MAX2233
900MHz ISM-Band, 250mW Power Amplifiers
with Analog or Digital Gain Control
Detailed DescriptionThe MAX2232/MAX2233 are nonlinear power amplifiers
(PAs) intended for constant envelope applications (FM,
FSK, GMSK). The devices operate over the 902MHz to
928MHz frequency range and provide typically 250mW
of output power and 44% efficiency from a single +2.7V
to +5.5V supply. Both devices typically provide 24dB of
gain, which is adjustable over a continuous 24dB range
through an analog voltage on CTRL of the MAX2232 or
in two 10dB steps through the 2-bit programmable gain
inputs (D0, D1) on the MAX2233. A low-power shutdown
mode on both devices reduces supply current to 0.2µA.
All bias, gain control, and temperature-sensing circuitry
is provided on-chip to save board space and reduce
component count. The signal path includes a variable
gain amplifier (VGA), an output driver, and an output
power transistor. On-chip interstage matching networks
are provided for optimal loading and power transfer.
Internal bias circuitry responds to CTRL and SHDNof
the MAX2232, or to the 2-bit gain/shutdown control
DAC of the MAX2233, providing optimum biasing and
efficiency as well as shutdown and ramp control func-
tions. A unique temperature-sensing circuit protects the
device from overheating by shutting down the PA until
a safe temperature is resumed.
The devices come in a 16-pin PQSOP package, which
incorporates a slug on the bottom of the device to
increase heat conduction and provide a low induc-
tance path to ground.
RF Input Stage (Variable Gain Amplifier)The input stage includes a variable gain amplifier
(VGA) with 24dB gain-control range. With the appropri-
ate matching network, the input VSWR is nominally
1.5:1 during operation and the change in VSWR is only
1.2:1, relative to normal operation. This stage remains
active during standby mode (MAX2232) to provide a
constant input impedance but is off during shutdown
mode (MAX2232/MAX2233). AC-couple this port with a
DC-blocking capacitor.
RF Second Stage (Driver)The driver provides gain to overcome interstage match-
ing losses and to produce a signal large enough to
drive the output power transistor into saturation. The
driver stage is off during standby (MAX2232) and shut-
down (MAX2232/MAX2233) modes.
RF Output Stage
(Output Power Transistor)The output power transistor delivers +24dBm of output
power from a single +3.6V supply. The transistor’s
open-collector output requires a pull-up inductor to
VCCfor proper biasing, as well as a proper output
matching network to ensure optimum output power.
Connect the output matching network to RFOUT (pin
8). See the Typical Application Circuitfor bias and
matching components suitable for 900MHz operation.
The ground of the output stage is connected to a metal
slug on the bottom of the MAX2232/MAX2233’s 16-pin
PQSOP package. The metal slug increases heat con-
duction and provides a low-inductance path to ground.
Solder the metal slug to the PC-board ground plane.
___________________________MAX2232
Analog Gain Control
and Power Management
Shutdown ModeDrive the shutdown (SHDN) pin below 0.6V to place the
MAX2232 in shutdown mode. The VGA, driver, and out-
put transistor are off in shutdown mode and the supply
current is typically reduced to 0.2µA. When SHDNis
above 2.0V, the device is enabled.
Standby ModeDrive SHDNabove 2.0V and CTRL below 0.4V to place
the MAX2232 in standby mode. In standby mode, the
VGA remains biased while the driver and output tran-
sistor are disabled. Supply current is typically 20mA in
standby mode. This mode allows the device to maintain
a good input VSWR while maintaining 38dB of isolation.
This is useful to users who drive the PA with a direct
modulated VCO, where pulling of the VCO results from
changes in the input VSWR.
Analog Gain ControlThe voltage applied to the gain-control (CTRL) pin varies
the output power of the MAX2232 continuously over a
24dB range. An internal comparator holds the PA to a
constant peak output power if VCTRLis above 2.2V. For
VCTRLbelow 0.4V, the PA is in standby mode. CTRL pre-
sents a high input impedance, allowing the VCTRLvoltage
to be set with a resistor-divider or a voltage output DAC.
Output Power AutorampingThe internal bias circuitry of the MAX2232 automatically
ramps the output power of the PA down or up at a con-
stant rate (in W/sec) when switched in or out of shut-
down mode. The output power is ramped to the level set
by VCTRLon the MAX2232. The output power rise and
fall time ramp is set by placing a capacitor, CRAMP,
between RAMP+ and RAMP-. This provides an easy
means of avoiding spectral splatter and complying with
transmit mask requirements, without using a separate
controller. The output power rise and fall time is set by
the value of CRAMP.
